The invention relates to a support and electrical power supply device for a multipole electrical switchgear apparatus comprising a parallelipipedic mounting plate with a case made of molded insulating material designed to be fitted on the parallel collecting bars of a busbar and containing:
branch conductors presenting identical lengths and extending perpendicularly to the busbar in adjacent compartments of the case, each conductor comprising at least one electrical connection strip for connection with a corresponding terminal of the switchgear apparatus and a contact strip designed to come into engagement with the collecting bar of the corresponding phase, PA0 connecting parts for connection between the terminals of the switchgear apparatus and the connection strips of the branch conductors, PA0 and securing means to secure the contact strips against the collecting bars of the busbar. PA0 said contact strips are situated in one and the same plane extending parallel to that of the connection strips with a predetermined offset, PA0 the connection strips are arranged close to the opposite terminal parts of the branch conductors and comprise orifices arranged symmetrically with respect to the horizontal midplane of the mounting plate to enable fitting of the connection parts with the lineside terminals or the loadside terminals of the switchgear apparatus, said electrical connection parts comprising conducting spacers of tubular shapes arranged between said lineside or roadside terminals and the corresponding connection strips of the branch conductors, fixing being achieved by means of clamping screws passing respectively through said terminals, the spacers and the associated orifices.
Such a device is described in the document DE 3,409,211 in which the branch conductors are coplanar, requiring conducting shims to be fitted between the collecting bars of the busbar and the bottom face of the branch conductors. Connection between the terminals of the switchgear apparatus and the strips of the branch conductors is achieved by means of connecting cables.
FIGS. 1 and 2 represent another support and power supply plate 10 of the prior art mounted at the level of the notched bottom face 12 on a three-phase busbar L1, L2, L3, and having an opposite top face 14 designed to receive an electrical apparatus 16, notably a circuit breaker. The collecting bars of the busbar L1, L2, L3 extend parallel to one another with a predetermined insulating offset and provide both mechanical support and electrical power supply of the apparatus 16. The mounting plate 10 comprises an insulating case 18 (in broken line) housing branch conductors D1, D2, D3 performing electrical connection between the collecting bars of the busbar L1, L2, L3 and the respective input terminals B1, B2, B3 of the poles of the apparatus 16. A system of screws 20 and spacers 22 performs the electrical connection between the terminals B1, B2, B3 and the branch conductors D1, D2, D3 of the mounting plate 10. The electrical connection between the branch conductors D1, D2, D3 and the collecting bars L1, L2, L3 is achieved by means of securing brackets (not represented) designed to clamp the branch conductors D1, D2, D3 against offset contact strips of the collecting bars L1, L2, L3. The branch conductors D1, D2, D3 are secured in individual compartments of the case 18 and present jointed shapes of different lengths extending perpendicularly to the collecting bars L1, L2, L3. The branch conductor D2 stops at the level of the bar L2 and the longest conductor D3 extends up to the bar L3. The connection strips for connection of the input terminals B1, B2, B3 with the branch conductors D1, D2, D3 are located appreciably in the same plane.
Side by side assembly of several mounting plates 10 is possible in the widthwise direction of the collecting bars L1, L2, L3 so as to form a low voltage distribution dispatcher.
Such a dissymmetry of the branch conductors D1, D2, D3 of this known mounting plate 10 requires precise positioning of the case 18 on the busbar L1, L2, L3 according to the choice of lineside or loadside feeders of the apparatus 16. In the case of FIG. 2, the power supply to the terminals B1, B2, B3 is performed lineside and the feeder is connected loadside. In the case of a lineside feeder, the mounting plate 10 has to be reversed one half-turn or the location of the branch conductors D1, D2, D3 in the respective compartments of the case 18 has to be modified. The possibilities of electrical distribution making use of such a mounting plate are limited to a given type of electrical installation and the connection possibilities are limited.